1. Field of the Invention
The present invention relates to a gaming machine that is capable of repeatedly executing a unit game.
2. Description of the Related Art
In a gaming machine adapted to repeatedly execute a unit game, there is proposed a technique of changing a payout rate by employing so called integrated symbols (for example, United State Patent Application Publication No. 2008/139294 and United State Patent Application Publication No. 2008/146314).
In recent years, in casinos outside Japan, there has been a tendency that popularity of slot machines lowers, whereas popularity of table games or the like rises. One of the causes is deemed to be a low payout rate of slot machines. Since managers of such casinos need to ensure a certain amount of sales, there is a tendency of avoiding installation of a slot machine with its high payout rate. That is, in a case where the payout rate is high in a state in which operability of a slot machine is identical to that of another one, the sales of game facilities decrease. Therefore, managers of game facilities such as casinos are likely to hesitate against introduction to a slot machine with its high payout rate. As a result, a player cannot enjoy the play of game sufficiently at a slot machine with its low payout rate, and therefore, fewer players play slot machine games, and the sales of the gaming facilities could not be increased.
In addition, a slot machine that is capable of changing a payout rate in gaming facility such as casino as well is conventionally known. In such a slot machine has a switch for changing the payout rate. In a gaming facility, after closing shop, the staffs can change setting of the payout rate by operating the switch according to a playing situation in the gaming facility. However, a player cannot directly check whether the payout rate is set to be high or low. Thus, even in a case where the payout rate is set to be high in a gaming facility, a player cannot be aware of the fact, and there has been a possibility that the player can enjoy a game at a slot machine, a payout rate of which is set to be high. Therefore, even in a case where the payout rate is set to be high, players who come to gaming facilities to play slot machine games cannot always enjoy the games, the number of players who play the games at slot machines cannot always be increased, and it has been difficult to increase the sales in gaming facility by slot machines.
Further, there is a slot machine at which the routine migrates from a basic game to a bonus game, based on the fact that a player has won a lottery in lottery processing, and then, a large amount of gaming mediums is intensively paid out. However, in such a slot machine, the number of payout in basic game is often defined to be extremely small in comparison with a bonus game. Thus, in a case where the routine has failed to migrate to a bonus game, a large amount of gaming mediums in bonus game is not paid out to a player.
Therefore, in the conventional slot machines as described above, there has been a tendency that players are given an impression that they cannot enjoy the games, even if there is provided a function that is capable of changing the payout rate or a function that is capable of acquiring a large amount of prizes such as bonus game.
The present invention has been made in order to solve the conventional problem as described above, and it is an object of the present invention to provide a gaming machine that is capable of causing a player to realize an attractive payout rate by advancing the play of game while causing the player to be impressed that a state advantageous to the player is established.